package org.bouncycastle.asn1.x509;

import java.util.Enumeration;
import java.util.Hashtable;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.DERSequence;

/**
 * PolicyMappings V3 extension, described in RFC3280.
 * 
 * <pre>
 *    PolicyMappings ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
 *      issuerDomainPolicy      CertPolicyId,
 *      subjectDomainPolicy     CertPolicyId }
 * </pre>
 * 
 * @see <a href="http://www.faqs.org/rfc/rfc3280.txt">RFC 3280, section 4.2.1.6</a>
 */
public class PolicyMappings extends ASN1Encodable {
    ASN1Sequence seq = null;

    /**
     * Creates a new <code>PolicyMappings</code> instance.
     * 
     * @param seq
     *            an <code>ASN1Sequence</code> constructed as specified in RFC 3280
     */
    public PolicyMappings(ASN1Sequence seq) {
        this.seq = seq;
    }

    /**
     * Creates a new <code>PolicyMappings</code> instance.
     * 
     * @param mappings
     *            a <code>HashMap</code> value that maps <code>String</code> oids to other <code>String</code> oids.
     */
    public PolicyMappings(Hashtable mappings) {
        ASN1EncodableVector dev = new ASN1EncodableVector();
        Enumeration it = mappings.keys();

        while (it.hasMoreElements()) {
            String idp = (String) it.nextElement();
            String sdp = (String) mappings.get(idp);
            ASN1EncodableVector dv = new ASN1EncodableVector();
            dv.add(new DERObjectIdentifier(idp));
            dv.add(new DERObjectIdentifier(sdp));
            dev.add(new DERSequence(dv));
        }

        seq = new DERSequence(dev);
    }

    public DERObject toASN1Object() {
        return seq;
    }
}
